基于全钒液流电池动态模型的电荷损失分析

Charge loss analysis based on dynamic model of all-vanadium redox flow battery

全钒液流电池的电荷损失主要由旁路电流和交叉反应共同引起。旁路电流与电解液的流道设计有关,交叉反应与隔膜的阻钒能力有关,在实际应用过程中两者相互耦合,各自占比并不明确。因此,有必要考虑旁路电流和交叉反应建立全钒液流电池系统模型来定量分析各部分电荷损失的大小,这将为提高电流效率提供重要依据。考虑旁路电流和交叉反应建立了动态模型,分析了交叉反应和旁路电流引起的电荷损失动态变化情况,电流和流量等运行参数对电荷损失率的影响。分析结果有助于在液流电池设计过程中提高电池性能,从而减少实验和设计的成本。

The charge loss of all-vanadium redox flow battery is mainly caused by shunt current and cross reaction.The shunt current is related to the design of the flow passage of the electrolyte,and the cross reaction is related to the vanadium resistance capacity of the diaphragm.In the practical application process,the two are coupled with each other,and the proportion of each is not clear.Therefore,it is necessary to establish a vanadium flow battery system model considering shunt current and cross reaction to quantitatively analyze the charge loss of each part,which will provide an important basis for improving current efficiency.The dynamic model of charge loss caused by cross reaction and shunt current is established,and the influence of operation parameters such as current and flow on charge loss rate is analyzed.The analysis results will be helpful to improve the performance of the liquid flow battery in the design process,thus reducing the cost of experiment and design.